Abstract. The possibility of plasma performance improvement in the ITER reference 15 MA scenario by pellet injection is considered. Fusion gain Q increasing by density peaking and controllable mitigation of the energy loss in the Type-I Edge Localised Modes (ELMs) by increase of the pedestal collisionality are analysed. Plasma scenario with Q = 20 within the Greenwald density limit is demonstrated. Requirements for pellet injection for the ELM loss reduction below 5% of the pedestal energy is considered.